Piano action



June 9, 1942. A. F. KNOBLAUGH 2,285,817

PIANO ACTION Filed April 10, 1941 INVENTOR Patented June 9, 1942 y j PIANO ACTION Armand F. Knoblaugh, Cincinnati, Ohio, assignor to The Baldwin- Company, Cincinnati, Ohio Application April 10, 1941, Serial No. 387,935

Claims.

My invention relates to piano actions and particularly to actions for small upright pianos currently known in the art as console pianos. A large part of the action in these small height instruments is below the keyboard level, and inproviding operative connections between the respective keys of the keyboard and the corresponding action members certain problems are involved, when the manufacturing and repair aspects of the instruments are considered. These problems may be outlined in the following objects of the present invention and their solutions ac cording to the invention set forth in its detailed. description.

Thus itis an object of the invention to provide connecting arrangement between the keys and action of a small upright piano, having the fundamental advantages of few parts and low cost of construction.

It is also an object to provide a key and action organization which, except for the connecting. arrangement between the keys and action, consists of a usualupright piano action and the usual intermediately pivoted keys.

Further objects are to provide a construction whereby keys may be readily removed and installed, whereby the action for the whole piano may be readily installed and removed as a unit, and whereby the adjustment for lost motion between keys and action may comprise the familiar capstan screw means.

It, is also an object toprovide an arrangement such that keyand action connectors may be readily installed and removed individually.

The manner in which the above objects are attained and the attainment of those objects which will be pointed out hereinafter or occur to those skilled in the art on reading this specification, will now be described in detail, reference being made to the accompanying drawing forming a part hereof, wherein:

Figure l is an elevaticnal View of an action constructed according to the invention, located in a small upright piano, the view being taken between adjacent notes of the piano;

Figure 2 is an elevational view, somewhat, enlarged with respect to Figure l, of a capstan screw employed in the invention;

Figure 3 is a plan view, similarly enlarged, of head member of a key and action connecting member; and

Figure 4 is an elevational view taken similar to Figure l, of an action shown in a position ready for removal from a piano.

Referring first to Figure 1, a small upright piano contains a keybed I supported by side arms (not shown) of the instrument. Attached on the bed I is a keyframe 2 supporting a keyboard of usual intermediately pivoted keys 3, the front manually operable portion of the keyboard, not shown, being of conventional con struction.

In accordance with the type of piano in which the present invention is employed an upright piano action 4 is disposed behind the keys 3 and partly below their level. This action may be organized according to usual practices in upright action construction, and thus has underneath a series of rearWa-rdly pivoted, forwardly extending wippens 5 supporting various action parts such as jacks 6 which operate upon the hammers l. The piano strings 8- struck by the hammers are of course disposed behind the action 4 in a vertical. plane.

For connecting the keys and action of a piano the invention provides a series of connecting members or abstracts 9, pivoted at their lower ends respectively to the forward ends of the \vi-ppens 5. These members 9 extend upwardly from their pivot points as rod-like structures located behind the keys 3, and each member has inan upper part thereof a rigidly attached forwardly extending head. member IO bearing upon a respective key in a manner to be de scribed. Preferably I make the connecting members and their head members of wood. For joining; them the rear ends of the heads I 0 are slotted centrally as shown at H in Figure 3, with the side faces of the members 9 as well as their front faces being correlatively slotted, the two parts thus fitting together similar to a mortiseand-tench type of joint and forming when glued a. strong rigid connection.

I also-slot centrally the front, ends of the heads it]. As illustrated at l2 in Figure 3 these slots are of open character extending rcarwardly from the front edges of the members I0 and vertically entirely through the members, thus forming two bearing arms l3", I3". The inner surface of each slot is bushed with cloth I 4.

As shown in Figure 1, each key 3 carries near its, rear end an upwardly extending metal capstan screw !5. The aforementioned Figure 2 particularly illustrates this screw. Its body portion comprises a threaded shank, whereby the screw is threaded into its key, and a head 16 adapted to application of an adjusting wrench. The top face of the head It is provided as a convex surface ll, and the remaining portion of the screw comprise a cylindrical metal pin l8, extending upwardly from the surface I! and co-axial with the screw body portion. This pin l8 may be driven into a tight hole provided in the head IE or it may be attached by welding to the head. Or as a further method of forming, the complete capstan screw may be die cast integrally of suitable metal.

The pins 18 are of such diameter that they will fit freely in the bushed slots l2. Thus as shown in Figure 1, the connecting members 9 engage their respective keys through the head member 19 bearing upon the capstan screws IS, the pins l8 being disposed within the slots [2 and the arms l3, I3 bearing upon the surfaces I1, an interposed felt washer l9 being provided on each pin.

In this way the playing movements of the keys'are translated to the members 9 and thus to the piano action 4, the pins l8 within the slots i 2 providing lateral guides for the members 9 in their up-and-down movements, the heads I rocking slightly on the capstan surfaces I! in these movements. As aforeindicated the capstan screws l are adapted to application of an adjusting wrench. They thus may be regulated vertically with respect to their keys, providing thus a means for eliminating lost motion between the keys and action, of a character familiar to piano technicians.

Since the slots l2 in the head members H! are open to the front, as above described, the keys may be removed from the instrument in a simple operation, similar to that of removing keys in large upright pianos. Insertion of keys is likewise a simple procedure.

AS above mentioned, the capstan pins It in conjunction with the slots 12 of the connecting member heads I! provide lateral guides for the connecting members in their up-and-down movements. It is of course also necessary that proper front-rear alinement of the members be maintained for the heads It to remain on the capstans l5 in operating. I have found however in this regard that proper front-rear alinement of the members maintains itself, i. e., the

members inherently walk forward in oper-- ating, until the rear ends of the slots l2 contact the pins 58. I am not certain of the exact cause of this. I believe however that it is owing to a combination of the fact that the centers of gravity of the connecting members are located forward of the pivot points of the members with the action wippens 5, and the probability that a slight forward drag is exerted upon the connecting member heads H] by the capstan screws I5 in their upward movements. (It will be noted that the upward movement of a capstan screw, corresponding to a playing blow delivered to the front end of its key 3, during which time relatively large force is exerted by the screw on the corresponding member I0, is in reality an arcshaped movement having a slight forward as well as an upward direction.)

As a precaution however that the members l0 remain normally on their capstans IS, the invention provides a rail 20 having its front face covered with a strip of felt 2|. This rail, as illustrated in Figure 1, extends parallel to the series of connecting members 9, somewhat below the upper ends of the members and slightly displaced rearwardly therefrom. It is supported by the interspaced action brackets 22 (of which there are usually four in a piano), being attached by screws 23 to forward extensions 24 of the brackets. The rail 29. when in the position of Figure 1, prevents the connecting members disengaging from the capstan screws, should the piano be tilted or overturned (as sometimes happens in transportation). It is also important in this regard that the pins l8 be of sufficient length. I find that a visible length of for the pins is adequate.

The rail 29 has another important function. For reasons well known in the art the entire action mechanism of a piano is comprised as a unified assembly for all the notes, installable and removable as such from the instrument, this assembly being integrated on rails, e. g., the rails 25 and 26 in the present drawing, rigidly attached to interspaced brackets, such as the action brackets 22.

Now it is desirable in the present invention that the operations of removing and installing the action be accomplished without the necessity of disconnecting the connecting members 9 from the action. Furthermore with the connecting members thus carried it is important that they be tied back compact with the action. To accomplish this the rail -20 is unscrewed from the bracket extensions 24 and placed in a position along the members 9 immediately in front of the members and immediately above the heads l0. Then using the rail 20 as a push rod the members 9 are moved rearwardly off the capstan screws l5 until the members and the rail reach the position shown in Figure 4. The rail is then rescrewed to the bracket extensions 24 as shown, and the action is ready for removal from the piano, accomplished by removing the nuts 21 securing the action to the bolts 28, tilting the action forward on the ball bolt supports 29 (see Figure 1) and then lifting it out of the instrument. Installation of the action is a generally corresponding reverse operation.

A preferred construction for pivoting the connecting members to the wippens is indicated generally in Figure l. A member 9 has a clearance slot 30 in its lower end and carries a metal pivot pin 3| transversely disposed in the slot and tightly fitting in the adjoining walls. The corresponding wippen 5 is provided with a transverse slot 32, bushed with cloth, in the lower side of the wippen near its front end. As illustrated the slot 32 is of keyhole shape having an enlarged inner portion in which the pin 3| pivots freely and a constricted portion interposed between the inner portion of the slot and its outer end. In this way the members 9 maintain engagement with the wippens normally but can be readily disconnected for repair or replacement. The particular pivot arrangement is also useful in the initial assembly of the piano.

Modifications, of course, can be made in the present invention without departing from its spirit, and being thus described those features of the invention considered to be patentable comprise:

I claim:

1. In an action for a low upright piano having a key, a capstan screw threadably secured in the top of said key. said screw providing a shoulder and an extension thereabove to be engaged by an abstract member, said screw being adjustable to vary the effective height of said shoulder above the top of said key, an abstract member operatively associated with said key for movement thereby, and a head structure on said abstract member having a substantially horizontally extending projection with a vertically extending aperture therein, said aperture being adapted to loosely receive said extension, with said projection seating on said annular shoulder, the positioning of said annular shoulder relative to the top of said key acting to define the limits of movement of said abstract member in response to movement of said key.

2. In a piano having a key and a movable playing member, means for operatively connecting said key and playing member including a projecting member supported on said key having a shoulder intermediate its ends and an extension extending upwardly from the shoulder, and a movable abstract having a downwardly extending portion positioned entirely rearwardly of the end of the key and a forward extension positioned over the end of the key when in playing position having an aperture extending therethrough for receiving the projecting member extension, with said projecting member extension being limited in its extension into the aperture ing members operatively associated with said playing members comprising rod-like members extending upward behind said keys having head structures extending forward over said keys, said head structures having each a vertically extending aperture therein adapted to receive loosely the said extension of a key projecting member and bearing each upon a corresponding key projecting member shoulder with said extension disposed Within said aperture.

4. The combination as set forth in claim 3, wherein said aperture in each of said head structures comprises a rearwardly extending opening in the front edge of the structure and including a rail member supported adjacently behind said connecting members, said rail member being readily disconnectable from its supports.

5. The combination as set forth in claim 3, wherein said aperture in each of said head structures comprises a rearwardly extending opening in the front edge of the structure wherein said action is supported on brackets having forward extensions, and including a. rail member supported on said forward extensions adjacently behind said connecting members.

ARMAND' F. KNOBLAUGH. 

